Hammer



May 7, 1929.

G. L. KO LLOCK Filed July 29, 1925 INVENTOR 'kw ya L. /f0//0A ATTORNEY l t lay W2 2 GEORGE ll KULLOCK, F fill lfltlli 'lllldl, WASHINGTON.

HAMMER.

Application filcdl July 29%, 1925. Serial Itl'o. lt-1,77%.

This invention relates to electrically con trolled spring-hammers and, more especially, to improvements in the hammer illustrated and described in U. S. Patent No. 1,224,471,

dated May 1, 1917.

The object of my improvements is to simplify the hammer construction and generally to render the device more convenient and ellicient in operation.

l lo these ends I provide a spring impelled striking member having a bifurcated upper portion, between the bifurcations of which revolves a power driven annulus having a cam edge which operates against a roller carried.

:l by said strikingmember to retract the latter in opposition to its impelling spring The invention further consists in the novelconstruction, arrangement and combination of parts hereinafter described and claimed.

In the accompanying drawing,-

Figure 1 is a longitudinal sectional view, partly in elevation, of an embodiment of my improved hammer. Figs. 2 and 3 are sectional views through 22 and 3-3 of Fig.

1. Fig. 4: is a perspective view of the cam member of the hammer.

[is shown in Fig. l of said drawing,the casing or shell of the device is formed to provide a tubular portion 5 into which extends the hammer or striking member 6 and containing the spring 7 which serves to effect the striking blows of said striking member.

tiaid shell also includes a portion 8 having therein a chamber 9 containing a motor 10 and the mechanism, hereinafter described,

which is operated by the motor for retracting thestriking member 6 in opposition to said spring.

[is illustrated, the striking member is cylindrical, is disposed axially of the casing part 5 and is guided by a bearing 11 provided in the door 12 of the chamber 9, and by a collar 16 of the striking member acting in the bore of such casing part.

Secured to the outer end of the casing part 5 is a tubular head piece which is provided desirably with a bushing 13 in which operates the shanlrf of a suitable die or tool such as denotedby 17, for example.

n The above referred .to spring 7 is of the helical type, surrounding the striking memher, one end of the spring acting against the casing floor 12 and its other end against the collar 16 which may be formed integral with the striking member or, as shown, in Figs. 1 and 3, separably connected thereto.

The manner now preferred by me for con necting the collar to the striking member is to provide within a circumferential groove of the latter, a two-part ring of greater external diameter than the striking member and confining the ring within a recess provided therefor in said collar.

The end of the striking member-within the chamber 9 is slotted longitudinally, as at 18, to adord two bifurcations 19, which latter are bored diametrically of the member for a pin 19 upon which is mounted, within the slot 18, a roller 20.

Seated upon the floor 12, referably, of the chamber 9 is an annular trac -plate 21 having in its upper surface a groove which serves as a runway for hearing balls 22 upon which is mounted a crown cam 23. This cam and the track plate 21 are disposed to have their axes coincide and in offset and parallel relation with respect to the axis of the striking-mem- .ber.

Furthermore, the track-plate 21 and the cam 23 are arranged to extend, as shown in Figs. 1 and 2, through the slot 18 of the striking member to cause the roller to track upon the cams helical surface or surfaces 2'4, two being shown.

25 represents an annular coupling provided adjacent one of its endswith an external peripheral flange engaging against a shoulder 26 provided in the inner periphery of the cam, said coupling extending through the aperture of the track plate 21 and having therebelow screw connection with threads 27 provided in the casing.

The cam 23 is rotated through the medium of suitable power transmission mechanism, including friction gears of known construction or, preferably, by employing toothed gearing as illustrated in the drawing. To such end the cam 23 is shown as provided circumferentially with spur gear-teeth 28 in mesh with the teeth of a pinion 29 which for illustrative purposes is mounted directly upon the armature shaft 30 ot' the electric the striking-member to successively com-.

press the spring 7.

When the high point 37 (Fig. 4) of a cam surface 24 revolves beyond the roller 20, the

striking-member becomes unsupported thereby, whereupon the spring asserts its power to effect a blow of the striking-member against the tool. The cam continuing to rotate carries the cam surface revolubly beneath the roller of the striking member and cooperates with the spring to produce intermittent re cipro -atory motion to the striking-member.

In the present invention it is to be noted that the cam imparts a retractive movement to the striking member by a force applied axially or approximately so, with respect to the striking member, thereby permitting rapid motion to the striking member with a minimum of friction and of heat.

This arrangement also eliminates to a large extentlateral vibratory motion whichis so objectionable to workmen.

While I have illustrated and described a construction and arrangement of parts now preferred by me, I do not wish to confine myself specifically thereto except as limited by the appended claims.

What I claim, is,

1. In apparatus of the class described, a

casing, a bifurcated striking member arranged for reciprocatory axial movements, a roller carried by said member in the opening between the bifurcations thereof, a power driven crown-cam eccentrically journaled relatively to the axis of the striking member and arranged to revolve through said opening, said cam being adapted to act against the roller for imparting motion to said member in one axial direction thereof, and a spring acting to impart axial motion to the member in the opposite direction.

2. A hammer of the class described comprising a cylinder having a tool slidahly extending through its outer end, a housing having a floor closing the inner end of the cylinder, a reciprocable striking member in the cylinder having a slotted inner end slidahly extending through the floor of the housing into the latter, a spring in the cylinder for driving the striking member outwardly against the tool, an annular crown cam journaled 0n the floor of the housing upon an axis parallel with the direction of movement of the striking member but eccentric thereto and passing through the slotted end of the latter, and a motor in the housing operatively connected to the cam for continuously rotating the latter to intermittently retract the striking member.

Signed at Seattle, \Vashington, this 16th day of June 192.

GEORGE L. KOLLOCK. 

